The structure of articular cartilage glycosaminoglycans in osteoarthritis patients: influence of knee topography
Quantitative and qualitative variations in glycosaminoglycan (GAG) content were studied in the revealed zones of degenerated, intact, and osteophytic cartilage of a human knee in osteoarthrosis (OA) (11 patients aged 65–75 years with Grade III of OA). Total glycosaminoglycan content was reduced in degenerated zone, unchanged in intact one, and raised in osteophytic zone of the cartilage. In degenerated cartilage zone the content of keratan sulphate was high and content of chondroitin sulphate was low. The ratio of chondroitin sulphate to keratin sulphate in osteophytic cartilage was high and thus resembled immature cartilage. In degenerated cartilage the ratio of sulfated glycosaminoglycan to uronic acids was very low, which can be considered as damage in GAG chains. A large amount of neutral hexoses and keratan sulfate is accumulated in zones of cartilage with biomechanical load and degeneration. Structure and metabolism of GAG are significantly different in zones of intact and degenerated cartilage in old patients with OA knee, which may be explained by changes in the phenotype of chondrocytes. Biomechanical stress provokes the development of the degenerative process.
About Authors (Correspondence):
Rusova T.V. – candidate of biological sciences, senior researcher of laboratory experimental department, e-mail: firstname.lastname@example.org
Baitov V.S. – senior researcher of department for endoprosthesis replacement, e-mail: VBaitov@1:st.ru